Hood construction for orchard heaters and the like



A. L. TODD Oct.- 15, 1957 HOOD CONSTRUCTION FOR ORCHARD HEATERS AND THE LIKE Filed Aug. 10, 1951 NVENTOR Aawwa L. has

flay rm ATTORNEYS iinited States Patent nice HOOD CONSTRUCTION FOR ORCHARD HEATERS AND THE LIKE Arthur L. Todd, San Dimas, Calif.

Application August 10, 1951, Serial No. 241,180

1 Claim. (Cl. 126-595) This invention relates to the construction of heaters of the bowl type adapted for the burning of carbonaceous fuels therein. More particularly, the invention has reference to heaters of this type, such as are commonly used in orchards, the present invention being a hood assembly for recirculation through the heater of gaseous products of combustion resulting from the burning of said fuel.

It is highly desirable in heaters of the type stated to eliminate or reduce as much as possible the smoke normally issuing from the heater and, understandably, it is also desirable to obtain a maximum amount of heat from a given quantity of fuel. The formation of large amounts of smoke is indicative of the incomplete combustion of the fuel, tending to deposit large quantities of soot and other undesirable residues within the heater. This materially reduces the efficiency of the heater. Additionally, a production of heavy smoke represents a considerable inconvenience to residents of the area, and hence is to be avoided as far as possible.

As will be appreciated, the problems of smoke elimination and insuflicient heat production have a close afiinity, since the elimination of the smoke by more complete combustion of the fuel has the natural result of adding to the efficiency of the heater so far as heat production is concerned.

It is, accordingly, one important object of the present invention to provide a smoke-clearing means for heaters of this type that will recirculate through the heater the hot, gaseous products of combustion in a manner to reduce or eliminate the discharge of smoke into the atmosphere, and obtain a more complete combustion of the fuel used in the heater.

More specifically, it is an object of the invention to provide a hood construction for heaters of the type stated, wherein said hood will be mountable upon an extension return conduit that is in communication with a main return conduit, the main return conduit having a connection to the stack of the heater for trapping and leading back to the bowl some of the hot products of combustion, the hood being adapted to trap the remaining products to lead them into confluence with the smoke or other hot gaseous products previously trapped.

Another important object is to provide a construction of the type stated that will be quite inexpensive and of a highly simplified design, since the use of structures of the type mentioned that are complex and expensive will outweigh the benefits to be gained thereby in a manner to render them commercially impracticable.

Referring to the drawings:

Figure 1 is a side elevational view of a heater formed in accordance with the present invent-ion;

Figure 2 is a sectional view taken on line 2-2 of Figure 1.

Referring to the drawings in detail, the illustrated construction is representative of a heater, such as that shown in my previous Patent No. 2,544,190, issued March 6, 1951. In that patent, a filtering apparatus was shown mountable upon the top of the stack conventionally pro- Patented Oct. 15, 1957 vided upon bowl-type orchard heaters. In the present invention, however, instead of a filtering means for clearing smoke, a hood is provided mountable upon and acting in cooperation with the recirculating or return conduit embodied in the patented construction.

Accordingly, there is illustrated a bowl 1 to be filled with .a suitable fuel, such as is commonly used for orchard heating, the bowl 1 being provided with the cover 2 in which is mounted a lighting spout 3.

Arranged concentrically of the dome-like cover 2 is a flanged opening 4 in which is mounted the lower end of a vertically disposed stack 5, through which the smoke and other gaseous products of combustion are discharged upwardly under normal conditions.

Formed in the marginal area of the cover 2 is an opening 6 in which is mounted the lower end of a vertically disposed return conduit 7 of lesser diameter than the stack 5, the return conduit being connected to'a T 8 at its other end. Secured to the laterally extending portion 9 of the T is one end of an L 10 extending through the side walls of the stack 5 adjacent the upper end of the stack, and opening downwardly into the stack. The L, as may be noted, is arranged concentrically of the stack, and is of substantially reduced diameter as compared. to the stack.

Thus, some of the smoke arising through the stack 5 will be trapped by the L and led through the T into the return or recirculating conduit 7, so as to be returned to the bowl 1 for the purpose of eifecting more complete combustion and reducing the amount of smoke discharged into the atmosphere.

At its upper end, the T 8 is connected to and is in full communication with the lower end of an extension return conduit 12 in which may be provided a damper 13 for regulating the draw through the extension conduit and return conduit. The extension conduit includes an L 14 that is mounted upon the upper end of the extension conduit, an L 15 being connected to the L 14 for imparting a return bend to the extension conduit at said upper end thereof.

As seen from Figure 2, the L 15 opens downwardly in vertically aligned, spaced relation with the stack 5, and in the downwardly opening end of the L 15 there is engaged the cylindrical neck 16 of a flared or frustoconical hood 17. The hood 17 is concentric with the main stack 5, and at its inlet end is of substantially increased diameter relative to the stack, said inlet end of the hood being preferably spaced vertically above the upper or outlet end of the stack.

in practice, when a suitable fuel, such as marine diesel or bunker grade, is burned within the bowl, incomplete combustion will ordinarily result, resulting in the production of a heavy quantity of smoke rising through the stack 5. As said smoke moves upwardly through the stack, a portion thereof is trapped by the connecting pipe disposed between the stack and return conduit, said connecting pipe comprising the portion 9 of the T 8 and the L 10. This portion of the smoke or other gaseous products of combustion is led downwardly through the re turn or recirculating conduit 7, so as to be discharged into the bowl 1, thereby to reduce the amount of smoke discharged into the atmosphere, and produce greater heat for a given quantity of fuel.

That portion of the gaseous products of combustion not trapped initially passes upwardly through the open upper end of the stack 5, and wil be trapped by the hood 17, so as to be led through the extension conduit 12 into confluence with the portion trapped by the L 10. Thus, the L 10 and hood 17 cooperate to cause practically all of the smoke discharged by the heater to be led back into the heater through a common recirculating conduit.

It will be appreciated, in this connection, that by adjustrnent of the pivoted damper 13, the draw through the recirculating passage can be adjusted as desired, depending upon the particular atmospheric conditions.

Although the invention has been illustrated as being embodied in an orchard heater, I believe that it is equally;

applicable to other types of heaters, such as incinerators and industrial smokestacl; installations.

What is claimed is:

The combination with a source of gaseous products of combustion and with a stack upstanding therefrom and open at its upper end for leading ofl said products, of a return conduit upstanding from said source; a connecting pipe communicating at one end with the return conduit, the other end of the connecting pipe opening downwardly through the side Wall of the stack to trap and lead 15 some of said products through the connecting pipe and into the return conduit for return thereof to said source; an extension conduit connected at one end to and extending, upwardly from the return conduit; and a downwardly opening hood on the other end of the extension conduit, said hood'being spaced vertically of and above the open upper end of the stack a substantial distance from the References Cited in the file of this patent UNITED STATES PATENTS 155,577 Gillen Oct. 6, 1874 314,697 Loveless Mar. 31, 1885 472,981 Burden Apr. 19, 1892 2,284,157 Leonard May 26, 1942 FOREIGN PATENTS 391,316 France Aug. 26, 1908 

